Electrode and cell



Jan. 25, 1947a C.' F.4 WALLACE 2,415,067

ELEoTRoDEs AND CELL Filed Aug. 18, 1939' l La:

u? 'r M l ATTORNEYS Patented Jan. 28, 1947 2,415,057 v generische AND onLL` Charles F. Wallace, Westfield,

N. J., assgnor to' Wallace de Yliernan `Products, Inc., Belleville,

N. Si.

, a corporation oi New Jersey Application August 18, 1939, Serial No. 290,841

` (Cl. ZIM-195) l Claims. 1

This invention relates to a method of and means for maintaining electrode surfaces `ina desired condition `for operation in contact with a liquid, and to `novel forms of electrodes.

One of the objects of the invention' is .toprovide a method of maintaining one or more liquidcontacting electrode surfaces in a desired condition for electrical operation.

Another object is to provide means for maintaining one or more liquid contacting electrode surfaces in a desired conditionforl electrical operation.

A further object is to electrodes.

An additional object is to provide a novel form of cell in which the electrodes are maintained in a desired condition during their electrical opera tion in contact with a liquid. i

Other objects and advantages of my invention will appear to those skilled in the art upon reading the following description of the invention and of the manner and process of making, constructprovide novel forms oi ing, compounding, and using it, and I shall also explain herein what I now believe to be the principle thereof, and the bestmode in which I have contemplated applying that principle.

Desiring to have it understood that my invention may be carried out by other means-and with other apparatus, and that it may be used in other environments and for other purposes, I shall now proceed to describe what Inow consider to Ibe a preferred form of apparatus for practicing the invention.

Referring to the drawing:

Fig. 1 is an elevation, largely in section, of a novel form of cell embodying the invention.

Fig. 2 is a horizontal section taken on the line 2--2 of Fig. 1.

Fig. 3 is an inverted detail plan view of the exposed electrode surfaces.

Fig. 4 is ahorizontal section taken on the line 4-4 of Fig. l.

Fig. 5 is a wiring diagram illustrating a simple type of circuit in which the cell shown in Figs. 1 to 4 may be employed.

The particular cell shown comprises a housing or container consisting of an intermediate transparent glass tube Iil clamped between end plates or blocks il, I2, of hard rubber, with interposed live rubber gaskets, the clamping being effected by a plurality of screw-threaded metallic rods or bolts I3.

The electrodes I fl, t5, preferably of gold, are secured to the underside or base of a cone It of `hard rubber. 1 One of the electrodes, I4, is a circuf `ing connectioni25 `at its lower lar disc and the other electrode, I 5, is an annular disc whose smaller diameter is greater thanthe diameter of the first mentioned disc, with which it is concentric.

Electrically conductive leads I l are each swaged to the top side of the electrodes M, I 5, and each electrically connected to acorresponding one of `the leads I8 which extend through a hard rubber `tube I9 which is screwed into the cone I6.-

.is screw-threaded into the hard rubber endtblock il and the sleeve 2l is screw-threaded intothe sleeve 2li. Upon unscrewing the sleeve LAI, the tube rI 9 maybe slid verticallyup or down, thereby adjusting the ,position ofthe electrodes Id, I5 in a vertical direction,.andithe `desired position of `adjustmentismaintained-by screwing the sleeve ZI intofthesleeveZlJto cause the packingA 22 to be compressed and grip the tubeJS. A gasket of live rubberis interposed between the shoulder of the `slee-ve 20iand-theupper'side of the block I I. By unscrewinglthe sleevel 2li, the electrode `assembly may be removed 4from thecontainer Ill-| I i2 for inspection or otherpurposes.

Liquid is introducedinto the` cell through the hard rubbertting 23 `which is screw-threaded into the lower endiblock I2, and which terminates in a nozzle 2li at its upper end and a hose-receivend.

`Liquid leaves the cell` throught/he hard rubber tting 2t, screw-threaded intofthe uppei` end block II and provided at'its outer end with a hose-receiving connection-,21. v

When the `parts arerassernbled, as shown,.the container or housing -Ill-I I I2 `.is liquid-tight,

,and no liquid Acanenter into orieave the inside of the housing except throughthe tting's23, 2,6.

-The block I2 is provided `with `an upwardly flaring frusto-conical opening 28, a cylindrical vbore 29, `and a second conical opening 30.

Yhard rubber, nxedlymounted-,in the cylindrical borejt, is provided with a `bore comprising opupwardly flaring frusto- AAVenturi member A3l, of

positely directed frustorconioal openings 32,` 33, terminating Aat their smaller ,diameters at the-cylindrical opening or throat Y34. The Venturi `memberl is exteriorlyshaped somewhat in the .form of triangular pyramids joined at their bases J so as to provide openings 35 (see Fig. 4) through which material may pass or drop from the frustoconical opening 28 into the frusto-conical opening 30.

The nozzle 24, in cooperation with the member 3I constitutes a venturi when liquid under suitable pressure or head is supplied through the fitting 23,

A suitable quantity of abrasive material is initially placed in the opening 30, or openings 28 and 30. The abrasive material consists of particles of Alundum, or garnet, or emery, or sand, or other suitable abrasive or scouring materials, or combinations of the same.

When liquid under suitable pressure is supplied to the tting 23, a jet thereof issues from the nozzle 24 and impinges upon the lower or exposed surfaces of the electrodes I4, I5.

Abrasive material, by the action of the jet in the Venturi member 3|, is automatically drawn into the opening 33 from the opening 30 and passes upwardly with the jet of liquid and im- -pinges against the surfaces of the electrodes I4, I which are exposed to the liquid. The liquid fills the interior of the cell and overflows or exits through the fitting 26. The abrasive material, being heavier than the liquid, is not carried out at the overflow 26 but, after impinging against the electrodes I4, I5, drops downwardly into the frusto-conical opening 28, then passes through the openings 35 (see Fig. 4) into the opening 30, whence it is again drawn into the bore of the Venturi member 3l. This operation is automatically carried on continuously as long as liquid under pressure is supplied to the tting 25 and no additional abrasive material need be added to the cell unless and until it has lost its sharpness, when it may be replenished or wholly new abrasive substituted.

The degree of scouring or scrubbing action of the abrasive upon the exposed electrode surfaces is dependent upon the dimensions of the particular cell employed, the specific gravities of the liquid supplied to the cell and of the abrasive, the character of the abrasive, the velocity of the jet of liquid discharged from the nozzle 24 through the body of liquid within the cell, etc. These factors are co-related or regulated so as to effect the removal of undesired material that would otherwise collect upon the exposed surfaces of the electrodes I4, I5, but without grinding or scouring away to any objectionable extent, the material of the electrodes themselves.

One of the many uses to which the cell may be put is in the detection of the residual chlorine content of water undergoing treatment by chlorine or which has been treated with chlorine, and one of the numerous circuits that may be employed is shown in Fig. 5.

The cell shown in Figs. 1 to 4 is indicated merely diagrammatically in dotted lines in Fig. 5, the two electrodes I4, I5 being shown in full lines. The cell I0 is shown connected in a circuit including a microammeter 36, a variable resistance 3l, a battery or cell 38, and a fixed resistance 39. Using a 1.5 volt cell 38, a variable resistor 31 of 5000 ohms, a xed resistance 39 of '750 ohms, and a potentiometer 40 connected in series with a g-alvanometer 4I across the resistor 39, and sup- -plying water containing residual chlorine to the cell I0, it was found that the current through the `cell l0 was a function of the amount of residual chlorine in the water, rising as the residual chlorine content is increased and vice versa. The current passing through the cell I0 may be measured with a microammeter 35, or the drop of potential across the fixed resistor 39 may be ascertained by so adjusting the slide of the potentiometer that the galvanometer il reads zero. 5 The polarizing current may be adjusted by the variable resistor 31 and set at any desired value with untreated water in the cell i0, and the readings of the meter 36, or the potentiometer 40, or both, correlated to the amounts or percentages of residual chlorine present in the water subsequently supplied to the cell I0.

The effect of the residual `chlorine in the water supplied to the cell I is to effect electrode depolarization, and consequent current increase, to an extent depending upon the amount of residual chlorine in the water. The utilized effect is one of depolarization and not one of change in conductivity or resistance of the liquid in the cell. For example, the addition of salt to the water, increasing its conductivity many times, has a practically negligible effect. Change in temperature of the liquid flowing through the cell does, however, afect the readings. In Fig. 1, 1 have shown a thermometer 42 suspended within the cell so that the temperature of the liquid may be readily ascertained. If this temperature does not change substantially, the readings may be relied upon without effecting temperature-compensating adjustments or recalibration. Preferably, the cell I0 is operated below the decomposition voltage of the liquid therein.

The scouring or scrubbing action of the abrasive material upon the electrode surfaces has a marked effect in stabilizing the action and operation of the electrodes and the cell. Any dirt, slime, or other deleterious matter that would otherwise deposit or accumulate on one or the other, or both, of the exposed electrode surfaces, is effectively removed therefrom by the scouring or scrubbing action of the abrasive.

As stated, the invention may be practiced by apparatus other than the particular construction shown and it may be utilized for other purposes and in different environments. For example, suitably -separated electrodes, each provided with a venturi for supplying liquid and abrasive thereto, may be employed in systems such as those disclosed in Letters Patent of the United States No. 1,944,803, patented January 23, 1934, on application led by Georg Ornstein. Again, one of the electrodes with its venturi for supplying liquid and abrasive thereto, may be employed in combination with a reference half cell in systems such as that disclosed in Letters Patent of the United States No. 2,070,964, patented April 13, 1957, on application led by Richard Pomeroy. My invention is especially adapted for use in systems, such as I have herein described, in which the effect utilized is a depolarization effect. However, it may also be used, with marked advantages, in indicating or control systems, or both, in which the eiect detected is a change of conductivity of a liquid. Also, as indicated above, my invention may be employed in cells in which changes in electrical potential are to be detected and utilized. The electrodes may both be made of the same materials or of different materials, depending upon the conditions of use and other factors. One or more of the electrodes may be made of platinum or other suitable material.

Some of my inventions disclosed but not claimed herein are being claimed in my application being filed of even date herewith and entitled Methods and systems of apparatus for detecting and controlling changes in composition r; of liquids, Serial No. 290,842, led August 18, 1989.

The velocity of the liquid entering the cell l0 and carrying the abrasive particles, is preferably maintained substantially constant by any suitable pressure regulating or head regulating device sc as not materially to affect the calibration of the cell. The vertical distance of the electrodes i4, l5 above the nozzle 2,4 i-s maintained at a predetermined height so as not materially to affect the calibration of the cell.

In accordance with the provisions of the patent statutes, I have herein described the principle of operation of my invention, together with the ap paratus which I now consider to represent the best embodiments thereof, but I desire to have it understood that the apparatus disclosed is only illustrative and that the invention can be carried out by other means. Also, while it is designed to use the various features and elements in the combinations and relations described, some of these may be altered and others omitted, without interfering with the more general results outlined, and the invention extends to such use within the scope of the appended claims.

What I claim is:

1. In a cell of the class described, in combination, a container, an electrode within said container, means for directing a jet of liquid against said electrode, and means including a Venturi device for introducing and entraining abrasive in the jet of liquid.

2. In electrical cell apparatus of the class described, in combination, a container, an electrode 6 in said container above the bottom thereof, an abrasive-receiving receptacle in the container below the electrode, the container havingr an overflow above the electrode, means for introducing liquid under pressure through said abrasive-receiving receptacle and for causing entrained particles of the abrasive to engage the exposed electrode surface and thereupon to sink before reaching the overflow, said last-mentioned means comprising means projecting the entering liquid as a jet of liquid alone, against the electrede and with sufficient velocity to advance the abrasive particles against the electrode solely by the now of the jet, a second electrode electrically associated t0 the liquid in the container, and means connected to said electrodes for detecting electrical effects representative of the chemical composition of the liquid.

3. A cell comprising in combination, a container having an outlet for liquid, a plurality of electrodes within the container and below the outlet thereof, a, Venturi device below the electrodes, and an abrasive receptacle below the electrodes and in communication with said Venturi device.

4. In a cell of the class described, in combination, a plurality of concentric electrodes having their exposed surfaces in substantially the same plane, means for directing a stream of liquid agai'nst the exposed surfaces of the electrodes, and means for entraining particles of abrasive in the liquid in its passage toward the electrode surfaces.

CHARLES F. WALLACE. 

